Equipe de Neuro-Ethologie Sensorielle, ENES/CRNL, University of Saint-Etienne, CNRS, Inserm, Saint-Etienne, France.
Division of Cognitive Science, University of Lund, 22100 Lund, Sweden.
Proc Biol Sci. 2022 Apr 27;289(1973):20220429. doi: 10.1098/rspb.2022.0429.
While nonlinear phenomena (NLP) are widely reported in animal vocalizations, often causing perceptual harshness and roughness, their communicative function remains debated. Several hypotheses have been put forward: attention-grabbing, communication of distress, exaggeration of body size and dominance. Here, we use state-of-the-art sound synthesis to investigate how NLP affect the perception of puppy whines by human listeners. Listeners assessed the distress, size or dominance conveyed by synthetic puppy whines with manipulated NLP, including frequency jumps and varying proportions of subharmonics, sidebands and deterministic chaos. We found that the presence of chaos increased the puppy's perceived level of distress and that this effect held across a range of representative fundamental frequency () levels. Adding sidebands and subharmonics also increased perceived distress among listeners who have extensive caregiving experience with pre-weaned puppies (e.g. breeders, veterinarians). Finally, we found that whines with added chaos, subharmonics or sidebands were associated with larger and more dominant puppies, although these biases were attenuated in experienced caregivers. Together, our results show that nonlinear phenomena in puppy whines can convey rich information to human listeners and therefore may be crucial for offspring survival during breeding of a domesticated species.
虽然非线性现象 (NLP) 在动物叫声中广泛报道，通常会导致感知刺耳和粗糙，但它们的交流功能仍存在争议。已经提出了几种假设：引起注意、传达痛苦、夸大身体大小和支配地位。在这里，我们使用最先进的声音合成技术来研究 NLP 如何影响人类听众对小狗叫声的感知。听众评估了经过 NLP 处理的合成小狗叫声所传达的痛苦、大小或支配程度，包括频率跳跃和亚谐波、边带和确定性混沌的不同比例。我们发现，混沌的存在增加了小狗的感知痛苦程度，并且这种效果在一系列具有代表性的基频 () 水平上都存在。添加边带和亚谐波也会增加有丰富照顾未断奶小狗经验的听众（例如饲养员、兽医）的感知痛苦。最后，我们发现添加了混沌、亚谐波或边带的叫声与更大、更具支配地位的小狗有关，尽管这些偏见在有经验的照顾者中减弱了。总之，我们的结果表明，小狗叫声中的非线性现象可以向人类听众传达丰富的信息，因此对于在驯化物种的繁殖过程中后代的生存可能至关重要。
